Set confluence permissions for a user account

Set-ConfluencePerms.ps1

Function Set-ConfluencePerms {
	[CmdletBinding()]
	param(
		[string]$user,
		[array]$groups,
		[string]$URL,
		$cred
	)
	# login to confluence
	$u = $URL
	$r1 = Invoke-WebRequest -Uri ( $u + '/login.action' ) -Method Get -SessionVariable s
	if ( $r1.StatusCode -ne 200 ) {
		 Throw "Failed to get Confluence login form."
	}
	$f = $r1.Forms[2]
	$f.fields.os_username = $cred.getnetworkcredential().UserName
	$f.fields.os_password = $cred.getnetworkcredential().Password
	$r2 = Invoke-WebRequest -Uri ( $u + $f.Action ) -Method $f.method -Body $f.Fields -WebSession $s 
	if ( $r2.StatusCode -ne 200 ) {
		Throw "Failed to login to confluence."
	}
	# request elevated permissions
	$r3 = Invoke-WebRequest -Uri ( $u + '/authenticate.action' ) -Method Get -WebSession $s
	if ( $r3.StatusCode -ne 200 ) {
		Throw "Failed to get admin authentication form."
	}
	$f = $r3.Forms[0]
	$f.Fields.password = $cred.getnetworkcredential().Password
	$f.Fields.destination = '/admin/users/editusergroups-start.action?username=' + $user
	# open the user edit page with elevated permissions
	$r4 = Invoke-WebRequest -Uri ( $u + $f.Action ) -Method $f.Method -Body $f.Fields -WebSession $s
	$f = $r4.Forms[1]
	# fill the user edit form with the user's groups
	$b = "?"
	$b += 'atl_token=' + $f.Fields.atl_token + '&'
	$b += 'username=' + $user + '&'
	$groups	| Foreach-Object {
		$b += 'newGroups=' + [uri]::EscapeDataString($_) + '&'
	}
	$b += 'save=save'
	# post the form to edit the groups
	$r5 = Invoke-WebRequest -Uri ( $u +  "/admin/users/" + $f.Action + $b ) -Method Post -WebSession $s
	if ( $r5.StatusCode -eq 200 ) {
		return $groups
	} else {
		Throw "Failed to set user groups."
	}
}